COMPLETE RESTORATION OF LACTATION IN THE GOAT AFTER HYPOPHYSECTOMY

Abstract

SUMMARY Studies have been carried out on the restoration and maintenance of lactation in six goats hypophysectomized during lactation. Three of these received replacement therapy some time after the operation when the milk yields had fallen to a very low level, and the other three received replacement therapy immediately after the operation. It was found that the combination of ovine prolactin (300 i.u. twice daily), bovine somatotrophin (12·5 mg./day or 6·25 mg. twice daily), triiodo-l-thyronine (0·5 mg./day), zinc protamine insulin (8 i.u./day) and tablet implants of dexamethasone could restore the milk yield to the pre-operative level when therapy was started some time after hypophysectomy. The same combination of hormones maintained milk secretion at the pre-operative level when therapy was started immediately after operation.